For proof that opposites attract, look no further than this must-have spring trend. A popular look for fall and winter, black and white has serious staying power, though warm-weather iterations come with shorter hems, flirtier cuts (think bell and shift dresses) and interesting patterns like checks or graphic prints. Need proof? Turn to the runways, where designers like 10 Crosby Derek Lam and David Koma used the dual hues in everything from high-contrast pantsuits to ulta-modern crop tops and skirts. Stay sleek with pulled-back hair and minimal accessories, as color is the enemy of this stark style. Welcome to the monochrome movement.